JP2008262157A - Dual image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem, wherein a dual image in which sub pixels of individual images for two visual directions are adjacent to each other in a gate line direction is liable to cause crosstalks in the gate line direction, by using an apparent crosstalk correction of less than one grayscale. <P>SOLUTION: The dual image display device 1 includes a crosstalk corrector 6 that corrects the grayscale of a sub pixel subject to correction, based on the grayscale of an adjacent sub pixel. The crosstalk correcting unit 6 carries out corrections, in addition correction data of K grayscale for N1 frames and corrections in addition correction data of K+1 grayscale for N-N1 frames within N frames where K is an integer, N is a positive integer of 2 or larger, and N1 is a positive integer smaller than N. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention displays on the same screen a screen capable of discriminating two individual images according to the viewing direction.
The present invention relates to a screen display device, and more particularly to a two-screen display device that performs crosstalk correction of less than one gradation.

Conventionally, a liquid crystal display device is used as a display device mounted on a television receiver or an information device.
Widely used. On the other hand, with the recent diversification of information devices and the like, a plurality of images are displayed on a single screen, the first image is provided in the first observation area, and the second image is displayed in the second observation area. There is known a two-screen display device that provides an image (see Patent Document 1 below).

The conventional two-screen display device will be described below with reference to the drawings. FIG. 18 is a cross-sectional view of a conventional two-screen display device. As shown in FIG. 18, in the two-screen display device 50 according to the conventional example, the first sub-pixel column 51 a that displays the first image and the second sub-pixel column 51 b that displays the second image are alternately arranged. The liquid crystal display panel 52 is provided. Here, each element unit of red, green, and blue (hereinafter referred to as RGB) is referred to as a sub-pixel, and the three sub-pixels of RGB are collectively referred to as a pixel (in the case of monochrome, not color, sub-pixel = pixel Become.). The first and second subpixel columns 51a and 51b are made up of subpixels of a liquid crystal display device, for example. Further, a black matrix 53 is formed between the pixels of the first and second subpixel columns 51a and 51b. A light shielding plate 54 made of metal or resin having a light shielding function is disposed above the liquid crystal display panel 52 via a transparent substrate such as a glass substrate having a thickness G (not shown). The light shielding plate 54 includes light shielding portions 55 and openings 56 that alternately extend in parallel to the first pixel row 51a and the second sub-pixel row 51b.

Next, a mechanism for realizing two-screen display by the two-screen display device 50 configured as described above will be described. As shown in FIG. 18, the opening 5 of the light shielding plate 54 is provided in the first observation region A leftward from the position C in front of the liquid crystal display panel 52 that is separated from the surface of the light shielding plate 54 by the distance D.
6, the first image is provided from the first sub-pixel row 51a. At this time, the second image of the second sub-pixel row 51 b is not provided to the first observation region A because it is blocked by the light-shielding portion 55 of the light-shielding plate 54.

On the other hand, a second image is provided from the second sub-pixel row 51b through the opening 56 of the light shielding plate 54 to the second observation region B that is separated from the position C in front of the liquid crystal display panel 52 in the right direction. . At this time, the first image of the first sub-pixel row 51 a is blocked by the light blocking portion 55 of the light blocking plate 54, and thus is not provided to the second observation region B. In this way, a two-screen display is performed in which the first image is provided in the first observation area A and the second image is provided in the second observation area B.

In such a two-screen display device 50, for example, when the two-screen display device 50 is arranged between a driver seat and a passenger seat in an automobile, the observation direction of the two-screen display device 50 is determined between the driver seat and the passenger seat. Therefore, it is possible to allow a person in the driver's seat to observe, for example, an image of a car navigation device, and to allow a person in the passenger's seat to observe other images.

However, it is generally known that when there is a large potential difference between adjacent sub-pixels in the liquid crystal display panel, the luminance level changes due to the potential difference. In the two-screen display device, images having different contents (for example, in the case of a navigation device, a navigation image is displayed in the driver seat direction and a DVD playback image is displayed in the passenger seat direction).
Since the sub-pixels are adjacent to each other, a large potential difference often occurs between the pixels.

This potential difference appears as crosstalk in the horizontal direction, which is the gate line direction, when displaying two screens. This phenomenon will be described with reference to FIG. FIG. 19A is a schematic diagram showing the left and right input images and an image at the time of two-screen display, and FIG. 19B is a diagram showing the luminance level for each pixel of the two-screen display device. In FIGS. 19A and 19B, the first observation position (left side) is surrounded by a triangular frame, and the second observation position (right side) is surrounded by a square frame. Are distinguished.

For example, as shown in FIG. 19A, when the left input image is composed of a central black box image and its surrounding halftone solid image, and the right input image is composed of a full halftone solid image,
At the time of two-screen display, the left image is displayed as the input image, but crosstalk occurs on the right side, and an area where the luminance changes is observed at a position corresponding to the left black box image.

The luminance level of each sub-pixel at this time is as shown in FIG. That is,
At the time of two-screen display, the luminance level of each sub-pixel does not change in the halftone solid area where the left and right input images are the same, but in the portion where the left input image becomes the black solid area, the pixel electrode corresponding to the left side Since the difference between the voltage applied to the pixel electrode and the voltage applied to the adjacent pixel electrode on the right side becomes large, the luminance of the right sub-pixel becomes an intermediate solid image as shown by the arrow in FIG. Pushed up from the corresponding brightness (may be lowered depending on the image to be displayed)
In the right display area, the luminance changes to a shape similar to the black solid area on the left side. This is 2
Horizontal crosstalk during screen display.

As a result of various studies to eliminate horizontal crosstalk in such a two-screen display device, the inventors have experimentally obtained in advance an amount of change in luminance caused by each gradation difference between adjacent sub-pixels. A correction data table is created, and the amount of change on the correction data table is obtained from the sub-pixel data to be corrected and the sub-pixel data on the right side of the two-screen composition to correct the sub-pixel data to be corrected. Is applied to all sub-pixel data to eliminate horizontal crosstalk.
JP-A-2005-258016 (Claims, paragraphs [0026] to [0036], FIG. 1)

However, the experimentally obtained correction data is not an integer, and unless this is converted to an integer, the driver of the liquid crystal panel cannot be driven, and there is a problem that crosstalk correction is performed in units of one gradation. .

In addition, in order to reduce the memory capacity, the inventors configured an even gradation matrix excluding the odd gradations in the correction data table, and the odd gradation correction data is an even gradation integer correction data. The method of calculating by interpolation was considered. In this case as well, there is a problem that the correction data for odd gradations does not become an integer but must be converted to an integer, resulting in crosstalk correction in units of one gradation.

It is also possible to perform regression analysis on the experimental data (by the least square method) to obtain a linear equation of gradation difference approximately from the correction data, and calculate the correction data from this linear equation. Although it is possible to calculate the correction data by a method other than the regression analysis, there is a problem that the correction data sometimes includes a decimal.

As described above, correction data may include decimal numbers in the interpolation of the experimental data and the correction data table, and the calculation of equations, but there is a problem that crosstalk correction is performed in units of one gradation instead of decimal correction. .

The present invention has been made in view of the above-described problems. Even if there is a restriction that the driver of the liquid crystal panel cannot be driven unless the correction data is an integer, the apparent crosstalk of less than one gradation is obtained. The purpose is to further reduce crosstalk by performing correction.

In order to solve the above-described problem, the two-screen display device of the present invention is configured to display gradations of luminance of subpixels, and the subpixels of individual images for two viewing directions are adjacent to each other in the gate line direction.
A two-screen display device comprising: a two-screen composition unit that outputs a screen image; and a crosstalk correction unit that corrects the gradation of the subpixel to be corrected based on the gradation of the adjacent subpixel,
The crosstalk correction unit performs the addition correction data of K (K is an integer) gradation in N (N is a positive integer less than N) frames in N (N is a positive integer of 2 or more) frames, and outputs K + 1 gradations. The addition correction data is subjected to N-N1 frames. As a result, the apparent crosstalk correction of less than one gradation can be performed, and the crosstalk can be further reduced.

In addition, a data table in which correction data corresponding to the gradation between adjacent sub-pixels in the gate line direction is obtained and stored in advance is provided, and the crosstalk correction unit corrects based on the data table.

Conventionally, even if correction data of less than one gradation is stored in the data table, correction can be performed only in units of one gradation. However, correction data of less than one gradation is stored in the data table and correction is performed in less than one gradation. can do.

The data table is composed of a matrix for every gradation and stores correction data for integer gradations, and the crosstalk correction unit interpolates the gradation correction data skipped every other gradation from the data table. Obtain by calculation.

Thereby, even if the correction data calculated by interpolation is not an integer, the apparent crosstalk correction of less than one gradation can be performed, and the crosstalk can be further reduced.

Further, the crosstalk correction unit is set to N = 4. This interpolation calculation is the average of two integers or 4
Since it is the average of two integers, the data calculated by interpolation are all the minimum units for correction.

Further, the crosstalk correcting unit mixes the sub-pixel for correcting the K gradation and the sub-pixel for correcting the K + 1 gradation in the same frame of the image in the same viewing direction.

Accordingly, flicker (flicker) caused by changing the gradation of adjacent frames by one gradation can be reduced.

Further, an image in the same viewing direction is composed of a plurality of blocks each having a predetermined number of sub-pixels as one block, and the order of correcting the K gradation and the K + 1 gradation in one cycle of N frames is determined. The array numbers are set from 1 to N so that the numbers from 1 to N of the array numbers assigned to the sub-pixels of one block are the same.

Thus, flicker can be reduced by distributing K + 1 gradations equally.

In addition, the sub-pixels of the individual images for the two viewing directions are arranged in a checkered pattern, and an image of the same viewing direction and a pair of red, green, and blue sub-pixels of the same gradation correction have one individual image V It becomes a character and the other individual image is a Λ character.

  Such regular distribution patterns can reduce flicker.

Also, the sub-pixels of the individual images for the two viewing directions are arranged in a checkered pattern, and the pair of red, green, and blue sub-pixels for the same viewing direction and the same gradation correction are the same for the two individual images. The direction is slanted.

  Such regular distribution patterns can reduce flicker.

The sub-pixels of the individual images for the two viewing directions are arranged in a checkered pattern, and the pair of red, green, and blue sub-pixels for the same viewing direction and the same gradation correction are arranged so that the two individual images are mutually connected. It is diagonal in different directions.

  Such regular distribution patterns can reduce flicker.

Also, the sub-pixels of the individual images for the two viewing directions are arranged in a checkered pattern, and the pair of red, green, and blue sub-pixels for the same viewing direction and the same gradation correction are arranged diagonally every other sub-pixel. It has become.

  Such regular distribution patterns can reduce flicker.

In addition, the sub-pixels of the individual images for the two viewing directions are arranged in a checkered pattern, and the pair of red, green, and blue sub-pixels for the same viewing direction and the same gradation correction are arranged with an odd number of frames. Different even-numbered frames are arranged.

  Such regular distribution patterns can reduce flicker.

In addition, the sub-pixels of the individual images for the two viewing directions are arranged in a checkered pattern, and the pair of red, green, and blue sub-pixels for the same viewing direction and the same gradation correction are either odd-numbered or even-numbered. The frame is diagonal and the other frame is V or Λ.

  Such regular distribution patterns can reduce flicker.

In addition, the image processing apparatus includes a selection unit that has a plurality of mixed patterns of the K gradation correction and K + 1 gradation correction areas and selects the pattern by external input.

  Thereby, the user of the electronic device can change the flicker mitigation pattern.

In addition, a plurality of modes having different values of N are provided, and a selection unit that selects the mode by an external input is provided.

  Thus, the user of the electronic device can change the correction gradation unit.

In addition, the luminance of the green sub-pixel in the same gradation is higher than that of the red sub-pixel and the blue sub-pixel, and the sub-pixels of the individual images for the two viewing directions are arranged in a checkered pattern, and the same viewing direction The sub-pixel arrangement in the image is that the green sub-pixel is not disposed in the six sub-pixels in the same viewing direction, which are the upper left, upper right, lower left, lower right, left, and right with the green sub-pixel as the center.

Thus, flicker can be reduced by preventing the green sub-pixels with high luminance from coming close to each other.

Further, the subpixels of the individual images for the two viewing directions are arranged in a checkered pattern, and K + 1 in which the subpixel arrangement in the image of the same viewing direction is performed for one frame K + 1 gradations in N frames.
The arrangement is such that three sub-pixels of the same color with the same gradation do not move to adjacent pixels twice due to a frame change.

In this way, it is possible to reduce the flicker because the K + 1 gradation is avoided as much as possible due to the change of the frame.

In addition, one screen is composed of three sub-pixels of red, green, and blue, and the gradation display of luminance of the sub-pixel is set, and the sub-pixels of the individual images for the two viewing directions are adjacent to each other in the gate line direction. A two-screen composition unit that outputs an image, and a crosstalk correction unit that corrects the gradation of the sub-pixel to be corrected based on the gradation of the adjacent sub-pixel,
The crosstalk correcting unit performs the correction of K (K is an integer) gradation in N (N is a positive integer greater than or equal to 2) N frames (N1 is a positive integer less than N) frame, and the correction of K + 1 gradation is performed. N-
N1 frames are composed of a plurality of blocks in which M1 is one sub-pixel in an image in the same viewing direction, and the order in which the correction of the K gradation and the correction of the K + 1 gradation is performed in N frames of one cycle. The determined array numbers are set from 1 to N so that the numbers from 1 to N of the array numbers assigned to one block of sub-pixels are the same, and the luminance of the green sub-pixel in the same gradation is the red sub-pixel. A two-screen display device having a luminance substantially L times that of a pixel and a blue sub-pixel,
The luminance of the green subpixel is calculated as L times the luminance of the red subpixel and the blue subpixel,
A group in which the number of sub-pixels to be determined and the number of adjacent sub-pixels is a total of M2 is set in one block,
The correction of all the sub-pixels of the one block is performed by correcting the K gradation by N-1 frames, and the K
When the correction of +1 gradation is performed for one frame, the time when the average luminance of one sub-pixel in one group is substantially the same as the average luminance of one sub-pixel in a block for all sub-pixels in one block is N frames. This is a pattern of assigning the sequence number to one block at least once.

In this way, the pattern in which the average brightness of the group is approximately equal to the average brightness of the block,
Flicker can be reduced.

Further, two screens in which one pixel is composed of three sub-pixels of red, green, and blue, gradation display of luminance of the sub-pixel is set, and sub-pixels of individual images for two viewing directions are arranged in a checkered pattern A two-screen composition unit that outputs an image, and a crosstalk correction unit that corrects the gradation of the sub-pixel to be corrected based on the gradation of the adjacent sub-pixel,
The crosstalk correcting unit performs the correction of K (K is an integer) gradation in N (N is a positive integer greater than or equal to 2) N frames (N1 is a positive integer less than N) frame, and the correction of K + 1 gradation is performed. N-
N1 frames are composed of a plurality of blocks in which M1 is one sub-pixel in an image in the same viewing direction, and the order in which the correction of the K gradation and the correction of the K + 1 gradation is performed in N frames of one cycle. A two-screen display device in which the determined array number is set from 1 to N and the number from 1 to N of the array numbers assigned to one block of sub-pixels is the same.
The correction of all the sub-pixels of the one block is performed by correcting the K gradation by N-1 frames, and the K
When one frame of correction is performed for +1 gradation, the frame order in which all sub-pixels of one block have the same color sub-pixel of the first adjacent pixel of the determination target sub-pixel as K + 1 gradation, and the determination target The frame order in which the sub-pixel has K + 1 gradation and the frame order in which the sub-pixel of the same color of the second adjacent pixel of the determination target sub-pixel has K + 1 gradation are not sequential.
It is the allocation pattern to one block of the array element number.

Thus, flicker can be reduced by a pattern with high brightness and little movement.

Hereinafter, the best embodiment of the present invention will be described with reference to the drawings. However, the embodiment shown below exemplifies a two-screen display device for embodying the technical idea of the present invention, and is not intended to specify the present invention. It is equally applicable to those of other embodiments within the scope.

FIG. 1 is a block diagram illustrating a main part of the two-screen display device according to the first embodiment. A solid line in FIG. 1 indicates the two-screen display device 1, and a broken line indicates the navigation device 30 in which the two-screen display device 1 is incorporated.

The two-screen display device 1 includes a liquid crystal panel 2, a signal processing circuit 3 that performs two-screen display processing of two source images (navigation image and DVD image) from the navigation device 30, and outputs them to the liquid crystal panel 2. Various data necessary for the operation (correction data table described later,
an EEPROM 4 for storing a mode, a ptn, and the like.

The signal processing circuit 3 includes a two-screen composition unit 5 that synthesizes two images, a crosstalk correction unit 6 that performs crosstalk correction, and a polarity and a signal so that signals corrected by the crosstalk correction unit 6 can be displayed on a liquid crystal panel. An output signal generation unit 7 that controls timing, an EEPROM controller 8 that controls input and output of the EEPROM 4, an i2c bus register 9 that transmits a signal from the navigation device 30 to the crosstalk correction unit 6, and an output and i2 of the EEPROM controller 8
A selection unit 10 for selecting one of the outputs of the c bus register 9 is provided.

The crosstalk correction unit 6 includes a preprocessing unit 11, a correction data sending unit 12, and a calculation unit 13, and the preprocessing unit 11 sends necessary data from the image signal from the two-screen synthesis unit 5 and sends correction data to the preprocessing unit 11. The correction data transmission unit 12 includes a LUT (lookup table) 14 that stores a correction table from the EEPROM controller 8 and a data interpolation unit 15 that interpolates data that is not in the LUT 14 to obtain correction data. The calculation unit 13 adds the correction data from the correction data sending unit 12 to the image from the preprocessing unit 11.

FIG. 2 is a diagram showing the pixels of the liquid crystal panel 2. The liquid crystal panel 2 is a color WVGA,
There are 800 pixels in the gate line direction (horizontal direction) and 480 pixels in the source line direction (vertical direction). One pixel is composed of three sub-pixels of RGB. As shown in FIG. 3, the liquid crystal panel 2 includes a liquid crystal shutter in which the light shielding pattern of the sub-pixels is a checkered pattern (a black and white pattern of a chess board).
As a result, one of the checkerboard patterns of the sub-pixels can be viewed only from the right direction (Japanese driver's seat direction), and the other can be viewed only from the left direction (Japanese passenger seat direction) (see FIG. 4). ). The sub-pixel has 6 bits, and the luminance of RGB is 2 6 to the 64th gradation. The drive control of the luminance of the liquid crystal panel 2 is in units of one gradation. That is, a gradation that is not an integer cannot be specified. The period of one screen (800 pixels × 480 pixels), that is, the frame period is 60 Hz.

FIG. 5 shows a correction data table. When 64 gradations are 0 to 63 gradations, this correction data table shows even gradations (0 gradations, 2 gradations, 4 gradations) for the correction target sub-pixel data and the right-side sub-pixel data. 64 (one gradation of 62 gradations) (64 gradations)
/ 2) × (64/2) = 32 × 32 matrix in addition to dummy auxiliary gradation (64 gradation) correction data, a 33 × 33 matrix. This is the final gradation (63 gradations)
Is obtained by interpolation calculation described later.

In each matrix, correction data experimentally determined from the correction target sub-pixel data and the right-side sub-pixel data are represented as 4-bit data of integer gradations, for example, as shown in Table 1, 3 is a sign bit, 3 bits from bit 2 to bit 0 are correction data, and correction data from −7 to 0 to +7 is stored. Since the minimum unit of gradation for driving the liquid crystal panel 1 is one gradation, the experimental data is rounded off to be converted into an integer and stored.

In FIG. 5, the portion where the code “0” is entered is a portion where correction is not necessary because the sub-pixel data to be corrected and the pixel data on the right side have the same value and horizontal crosstalk does not occur. The correction target sub-pixel data is the minimum value “0” or the maximum value “63”, and horizontal crosstalk does not occur regardless of the pixel data on the right side. In FIG. 5, all the correction data other than the portions that do not need to be corrected because the horizontal crosstalk described above does not occur is omitted, but an integer value of −7 to 0 to +7 is entered.

The EEPROM 4 stores data excluding the portion of the code “0” entered in FIG. 5, that is, (33 × 33−33 × 3 + 2) × 4 bits = 992 × 4 bits. This experimentally determined data stored in the EEPROM 13 is stored in the random access memory RAM from the EEPROM 4 when the power switch is turned on.
And is expanded as shown in FIG.

The two-screen display device 1 of the present invention has three modes: a 1 gradation unit crosstalk correction mode, a 0.5 gradation unit crosstalk correction mode, and a 0.25 gradation unit crosstalk correction mode. This selection is made based on 2-bit mode data as shown in Table 2, and the mode data is stored in the EEPROM 4. Also, the mode data is the navigation device 3
It is possible to input from 0 to the two-screen display device 1, and which mode data is used is selected by the i2c / EEPROM selection signal from the navigation device 30.

First, the 0.25 gradation unit crosstalk correction mode (mode = LH) will be described.

As shown in FIG. 3, the two-screen composition unit 5 includes a navigation unit 31 of the navigation device 30.
The 800 pixel × 480 pixel navigation image input from the DVD and the 800 pixel × 480 pixel input from the DVD playback unit 32 are selected in a checkered pattern of subpixels, and one 800 pixel × 480 pixel image is synthesized. .

The pre-processing unit 11 of the crosstalk correction unit 6 outputs the sub-pixel data to be corrected from the synthesized image input from the two-screen synthesis unit 5 to the correction data transmission unit 12 and the calculation unit 13, and the sub-pixel data on the right side is output. It outputs to the correction data transmission part 12.

In the correction data transmission unit 12, the power supply to the two-screen display device 1 is started and at the same time the EEP
The correction data table stored in the ROM 4 is transferred to the L through the EEPROM controller 8.
It is read into the UT 14.

The correction data transmission unit 12 reads the corresponding correction data from the gradation of the subpixel to be corrected and the gradation of the subpixel adjacent to the right from the LUT 14. At this time, since the correction data table is every other gradation, the correction data is interpolated by the data interpolation unit 15 in the case of an interval (odd gradation).

The operation of the data interpolation unit 15 of the correction data sending unit 12 is as follows. That is,
When the data at the four locations in the Z portion in FIG. 5 are, for example, LU, RU, LD, and RD as shown in FIG. 6, when the correction data falls between LU and RU, (LU + RU) / 2. As
When the correction data falls between LU and LD, it is (LU + LD) / 2, and when the correction data falls between RU and RD, it is (RU + RD) / 2, and the correction data is LD and R.
(LD + RD) / 2 if it falls between D, and further, the correction data is LU and RD.
Can be obtained as (LU + RU + LD + RD) / 4. L
Although data for all gradations may be developed on the UT 14, if such a configuration is adopted, the amount of data stored in the EEPROM 4 can be reduced, and the size of the LUT 14 is reduced, so that the LUT 14 can be rapidly operated. Since the interpolation itself can be calculated easily and at high speed, a two-screen display device having a smooth display and good display image quality can be obtained.

In the above-described interpolation calculation, the addition of integers LU, RU, LD, and RD is added by 2 or 4, so that the correction data obtained by interpolation has a gradation of 0.25 unit. However, since the driving of the liquid crystal panel must be an integer number of gradations, the present invention can correct K gradation and
+1 gradation correction is mixed. Further, if all the sub-pixels in one frame are set to K + 1 gradation, flicker (flicker) is likely to occur. Therefore, as shown in Table 3, the arrangement of sub-pixels for correcting K + 1 gradation is divided into four types of 1, 2, 3, and 4 and distributed in four frames.

Although the correction data stored in the correction data table of the above-described embodiment is a 4-bit integer, it can be stored as a value including a decimal. In this case, crosstalk correction can be performed for not only the odd gradation to be interpolated but also the even gradation for less than one gradation.

For example, when the correction calculated by interpolation is 1.25 gradation, the first frame (4n
A correction of 2 gradations is performed for the array 1 of the sub-pixels in the third frame), and a gradation of 1 is corrected for the arrays 2, 3, and 4. Two gradation corrections are performed for the sub-pixel array 2 in the second frame (4n-2 frame) of the four frames, and one gradation correction is performed for the arrays 1, 3, and 4.
Two gradation correction is performed for the array 3 of the sub-pixels in the third frame (4n-1 frame) of the four frames, and one gradation correction is performed for the arrays 1, 2, and 4. Two-tone correction is performed on the array 4 of the sub-pixels in the fourth frame (fourth frame) of the four frames, and the arrays 1, 2, and 3 are corrected.
1 gradation correction is performed for.

Thus, the correction order of the four frames is 1, 0, 0, 0 for the array 1, 0, 1, 0, 0, 0 for the array 2, and 0, 0, 1, 0 for the array 3. , The array 4 is 0, 0, 0, 1 and the timings of K + 1 gradation correction are different.
In the case of correction with 0.5 gradations after the decimal point, K + of array 1 and array 3 and array 2 and array 4
The timing of one gradation correction is the same.

7, 8, and 9 show four patterns of arrangements 1, 2, 3, and 4. 7 is a screen with a viewing direction on the left (12 subpixels × 8 subpixels), and FIG. 8 is a screen with a viewing direction on the right.
Is a screen that combines left and right. In each of FIGS. 7, 8, and 9, four types of 0.5 gradation unit correction patterns are shown on the left, and four types of 0.25 gradation unit correction patterns are shown on the right. The 0.5 gradation unit correction pattern is the same as the array 1 in the array 3 of the 0.25 gradation unit correction pattern to the right and the array 4 is the same as the array 2, and the pattern setting is the same. It is. 7 and 8, in the patterns 2-1 and 4-1, the RGB pairs of the array 1 and the array 3 are arranged diagonally downwardly every other subpixel, and the RGB pair of the array 2 and the array 4 is one sub. They are lined up diagonally at every pixel. In the pattern 2-1, RGB pairs arranged in arrays 1, 2, 3, and 4 are arranged horizontally. In the pattern 2-2 and the pattern 4-2, RGB pairs arranged in the arrays 1, 2, 3, and 4 are arranged diagonally downwardly to the right. Pattern 2-3 and Pattern 4-3 are array 1
And the RGB pairs of the array 4 are arranged obliquely upward and to the right, and the RGB pairs of the arrays 2 and 3 are arranged obliquely downward and to the right. In the pattern 2-3, RGB pairs arranged in an array 1, 2, 3, 4 are arranged in a V character form and a Λ character form. Patterns 2-4 and 4-4 are array 1 and array 3
RGB pairs are arranged diagonally to the right, and the RGB pairs of arrays 2 and 4 are arranged in a V-character form.

Since the frame period is 60 Hz, an apparent retinal image effect can be obtained by mixing K gradation correction and K + 1 gradation correction in a frame of N (N is a positive integer of 2 or more) period in this way. Correction in units of less than one gradation can be performed.

In addition, since the arrangement of sub-pixels for K + 1 gradation correction is divided into four types of arrays 1, 2, 3, and 4 and distributed in four frames, in other words, K gradation in one frame. Since the correction and the correction of the K + 1 gradation are mixed, the occurrence of flicker can be reduced. As shown in FIGS. 7, 8, and 9, the arrangement patterns of the arrays 1, 2, 3, and 4 are uniformly distributed by various regular patterns, and the occurrence of flicker can be further reduced. In addition, although the above-mentioned light-shielding pattern was a checkered pattern, this invention can be applied to various patterns, such as a stripe (vertical stripe) pattern.

As shown in Table 4, the four patterns shown in FIGS. 7, 8, and 9 are selected by 2-bit ptn. The ptn data is stored in the EEPROM 4 as in the case of the mode. The ptn data can also be input from the navigation device 30 to the two-screen display device 1. Which ptn data is used depends on i2c / EEP from the navigation device 30.
Selected by ROM selection signal.

Table 5 shows correction data for correcting the correction target sub-pixel. This correction data is 4-bit h [3: 0] and differs depending on the mode. Since the above example is 0.25 gradation unit correction with mode = LH, the correction range is narrow from -1.75 gradation to +1.75 gradation. However, the correction range can be easily widened by increasing the number of bits of h [3: 0].

As described above, the correction data sending unit 12 outputs correction data to the arithmetic unit 13 for each frame based on the mode and pattern specified by mode and ptn and based on the correction data table. Then, the calculation unit 13 obtains corrected sub-pixel data by adding the correction data sent from the correction data sending unit 12 to the correction target sub-pixel data sent from the pre-processing unit 11, and this correction. The subsequent sub-pixel data is sent to the output signal generator 7. The output signal generation unit 7 controls the polarity and timing so that the signal corrected by the crosstalk correction unit 6 can be displayed on the liquid crystal panel 2 and outputs the signal to the liquid crystal panel 2. Such correction of subpixel data is sequentially performed in the right direction by one subpixel for all subpixel data.

In the above-described embodiment, the correction data table has every other gradation, so the 0.25 gradation unit correction mode is set in accordance with the unit of the correction data. However, the 0.5 gradation unit correction mode and the 1 gradation unit correction mode have a disadvantage that the crosstalk is inferior to the 0.25 gradation unit correction mode, but are at a level that can be commercialized. As shown in Table 5, the 0.5 gradation unit correction mode and the 1 gradation unit correction mode have an advantage that the correction range is wide. Therefore, in the present invention, the i2c bus register is provided, and the mode can be selected by the user.
A flicker mitigation pattern is also provided by an i2c bus register and can be selected by the user.

In the first embodiment, the K gradation and the K + 1 gradation in one frame are mixed in four regular patterns. In the second embodiment, a method for quantifying the flicker determination based on the flicker factor is considered. Based on this value, a pattern in which flicker is unlikely to occur is generated.

In the patterns of FIGS. 7 to 9, blocks of six subpixels in the horizontal direction and four subpixels in the vertical direction are repeatedly arranged. As described above, normally, subpixels of a predetermined unit block are repeatedly arranged. Therefore, in the second embodiment, quantification is performed assuming that 6 (horizontal) × 4 (vertical) sub-pixels are arranged as one block.

As shown in FIG. 10, it is a checkered two-screen display device, which performs three frames of 20 gradations, 2
A screen in the right viewing direction when one gradation is performed for one frame and an apparent 20.25 gradation is performed will be described as an example. In FIG. 10, the diagonal line rising to the right indicates R (red), the shade of about 10% (thin) is G (green), and the shade of about 20% (darker) is B (blue). "And" 21 "
Indicates a gradation value. The pattern number in FIG. 10 is 4-5. Since one pixel is a square, the sub-pixel is a rectangle.

Table 6 is a table in which the order of 20 gradations and 21 gradations is assigned in 4 frames in one cycle. 4
There are types assigned, and these four types are numbered as array numbers. The array number H has 21 gradations in the H frame of one cycle. For example, SEQ ID NO: 2 has 21 gradations in the second frame,
There are 20 gradations in the first, third and fourth frames.

FIG. 11 is a diagram showing the four frames of FIG. 10 with the array numbers “1” to “4”.

As flicker elements, there are non-uniform luminance within a frame and changes in luminance within the frame.
Flicker is less likely to occur when the brightness is evenly distributed without shifting. In addition, flicker is less likely to occur if the sub-pixels with high luminance do not appear to move as the frame changes, as in a moving image.

First, the uniformity of luminance will be described. A screen in the right viewing direction of one block with 6 (horizontal) × 4 (vertical) subpixels has 9 subpixels with 20 gradations and 3 subpixels with 21 gradations. Also,
There are four green colors in one block. As shown in the gradation-luminance curve of FIG. 12, in the same gradation, red and blue have substantially the same luminance, and green has about four times the luminance of red and blue. Since green is a color that people feel high in luminance, the green luminance is set higher than red and blue in the same gradation so that the liquid crystal panel feels bright.

Therefore, the change in luminance due to one gradation UP is calculated. When one frame of one block of the screen in the right viewing direction is extracted that is brighter than 20 gradations, 21 gradations of RGB are each 1
There is one by one. The luminance of R and B in the same gradation is substantially the same, and G is about four times the luminance of RB. Therefore, if the level of the luminance difference between the 20 gradations and the 21 gradations of R is 1, 1 block One frame is UP of 1 + 4 + 1 = 6 levels. The number of sub-pixels in the right viewing direction of one block is 12
Therefore, it is only necessary to arrange 21 gradation sub-pixels and G so that the average is 0.5 level UP per sub-pixel.

A specific method will be described. As shown in FIG. 13, the reference sub-pixel and the upper left, upper right, left, right,
A total of seven of the six adjacent subpixels in the lower left and lower right are considered as one group. Sub-pixel is rectangular (
RGB is a square with three sub-pixels). Therefore, the upper and lower subpixels are not included in the group because they are separated from the reference subpixel. Then, since the number of subpixels in one group is seven, it is ideal that the luminance of one group is 0.5 level × 7 = 3.5 level. However, since the level summation is an integer, 4 levels are made ideal by rounding off.

  Table 7 is a table in which the brightness difference level in FIG. 13 is calculated.

The calculation method is that the reference subpixel and the six adjacent subpixels have 20 gradations unless the array number is equal to the current frame number in one cycle, so there is no luminance difference and the level is 0. . If the array number is equal to the current frame number in one cycle, level 1 is set for red and blue, and level 4 is set for green. The level is summed every 1st frame, 2nd frame, 3rd frame, and 4th frame.
If it is not 4th level, the point is set to 0.

48 points (uniform luminance) of 4 frames × 12 sub-pixels are obtained for one block. It is determined that the larger the total point is, the less likely flicker occurs due to uneven brightness.

In this way, a group including a sub-pixel to be determined and its adjacent sub-pixels is set, and when the average luminance of one sub-pixel in one group is substantially the same as the average luminance of one sub-pixel in the block, the point of addition is set. Points are obtained for all sub-pixels in one block, and further points are obtained for 4 frames and summed. Thus, since it quantifies based on average brightness | luminance, the determination of the flicker by nonuniform brightness | luminance can be performed. In addition, since green with high luminance is taken into account, highly accurate quantification can be performed. A pattern with reduced flicker can be obtained by this determination of quantification.

Next, a change in luminance will be described. 14 and 15 are diagrams showing examples of bad patterns. In FIG. 14 and FIG. 15, the frame number of the same color is increased by 1 downward, and appears to wave downward as the frame changes.

Therefore, the array number of the same color sub-pixel of the upper right adjacent pixel and the same color sub pixel of the lower right adjacent pixel (see the position in FIG. 16) is a number that forms three consecutive numbers with the array number to be determined as the center position. If it does, the point is set to 0, and if it does not become three sequential numbers, the point is set to 1 because it is difficult to generate flicker. Here, the adjacent pixels refer to eight pixels that are oblique in the vertical and horizontal directions in the arrangement of FIG. The three serial numbers may be either ascending order or descending order, and 1 and 4 are serial numbers.

Twelve points (luminance change) of 12 subpixels are obtained for one block. It is determined that flicker due to a change in luminance is less likely to occur as the total point is larger.

As described above, the frame order in which the subpixel of the same color of the upper right pixel of the determination target subpixel has 21 gradations, the frame order in which the determination target subpixel has 21 gradations, and the right of the determination target subpixel The point of addition is determined when the three sub-pixels of the same color of the lower pixel have 21 gradations and the three frame orders are not consecutive. That is, since the frame change movement of the high-luminance sub-pixel of the same color is quantified, flicker due to a change in luminance can be determined. A pattern with reduced flicker can be obtained by this determination of quantification. In addition, when the above-mentioned moving directions are ascending order and descending order, that is, upper right adjacent, judgment target, lower right adjacent array numbers are 1, 2, and 3 in ascending order, move from lower left to lower right with reference to upper right adjacent, When the array numbers of the upper right neighbor, the determination target, and the lower right neighbor are in descending order of 3, 2, 1, the upper right neighbor moves from the upper left to the upper right. However, the moving direction may be another direction. In other words, the point of addition may be used when the arrangement is such that the frame does not move to two adjacent pixels (up, down, left, right, and diagonal eight pixels) due to a frame change.

Forty-eight luminance uniform points and twelve luminance change points are summed. It is determined that the total flicker is less likely to occur as the total point is larger.

FIG. 17 is a diagram illustrating an example of a pattern having a large total point. This pattern number is 4
Set to -5. In the pattern 4-5, the same group is arranged so that there is one green color, and adjacent arrangement numbers of the same color are arranged so as not to have three consecutive numbers. As shown in FIG. 17, the luminance uniformity point of each sub-pixel is 1, the luminance change is point 1, and the total of the points is 24.

In the second embodiment, one out of four frames is an FRC having a decimal number of 0.25 gradation and one luminance higher, but this can be applied to a decimal number of 0.5 gradations and a decimal number of 0.75 gradations. The decimal number 0.5 is considered to be twice the decimal number 0.25 gradation and the array number 4 is changed to 2 and 3 is changed to 1. The decimal number 0.75 gradation is the sign of the decimal number 0.25 gradation. It can be applied as it is considering the opposite.

Although the correction data table described above stores integer correction data, it may be an experimental value including a decimal number. When the frame cycle at this time is N, the correction data may be set to 1 / N gradation units.

Moreover, although the above-mentioned Example was a liquid crystal panel, this invention can be applied also to organic EL.

It is a block diagram which shows the principal part of the 2 screen display apparatus of an Example. It is a figure which shows the pixel arrangement | sequence of a liquid crystal panel. It is a figure which shows the synthesis | combination of the separate image with respect to two viewing directions, and the checkered sub pixel arrangement | sequence. It is a figure which shows the display of the separate image with respect to two viewing directions. It is a figure which shows a correction data table. It is a figure which shows the method of carrying out the interpolation calculation of the gradation correction data which are not stored in the correction data table. It is a figure of the left vision direction which shows four patterns for preventing a flicker. It is a figure of the right view direction which shows four patterns for preventing a flicker. It is a figure of the left / right viewing direction which shows four patterns for preventing a flicker. It is a figure which shows the example of a pattern of 20 gradation / 21 gradation in flicker determination. It is a figure which shows FIG. 10 by a frame number. It is a gradation value-luminance diagram showing that the luminance of green is high. It is a figure which shows a group when performing the flicker determination by nonuniform brightness | luminance. It is a figure which shows the example which is easy to produce the flicker by the change of a brightness | luminance. It is a figure which shows FIG. 14 by a frame number. It is a figure which shows the position of the sub pixel of the upper right and lower right of the judgment object by the change of a brightness | luminance. It is a figure which shows the calculation result of a point. It is sectional drawing of the liquid crystal 2 screen display apparatus which concerns on a prior art example. FIG. 19A is a schematic diagram showing the left and right input images and an image at the time of two-screen display, and FIG. 19B is a diagram showing the luminance level for each pixel of the liquid crystal two-screen display device. .

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 2 Screen display apparatus 2 Liquid crystal panel 3 Signal processing circuit 4 EEPROM
5 2 screen composition unit 6 crosstalk correction unit 9 i2c bus register 10 selection unit 11 preprocessing unit 12 correction data transmission unit 13 calculation unit 14 LUT
15 Data interpolation part

Claims (18)

A sub-pixel luminance gradation display is set, and a two-screen composition unit that outputs a two-screen image in which sub-pixels of individual images for two viewing directions are adjacent to each other in the gate line direction, and a gradation of a sub-pixel to be corrected A two-screen display device including a crosstalk correcting unit that corrects the image based on the gradation of the adjacent sub-pixels,
The crosstalk correcting unit performs the correction of K (K is an integer) gradation in N (N is a positive integer greater than or equal to 2) N frames (N1 is a positive integer less than N) frame, and the correction of K + 1 gradation is performed. N-
A two-screen display device that performs N1 frames. The data table according to claim 1, wherein correction data corresponding to gradations between adjacent sub-pixels in a gate line direction is obtained and stored in advance, and the crosstalk correction unit performs correction based on the data table. 2. The two-screen display device according to 1. The data table is composed of a matrix for every other gradation and stores correction data for integer gradations, and the crosstalk correction unit interpolates the correction data for gradations skipped every other gradation from the data table. The two-screen display device according to claim 2, wherein the two-screen display device is obtained. The two-screen display device according to claim 3, wherein the crosstalk correcting unit sets N = 4. 2. The crosstalk correction unit, wherein a sub-pixel that corrects the K gradation and a sub-pixel that corrects the K + 1 gradation are mixed in the same frame of an image in the same viewing direction.
2. A two-screen display device. An image in the same viewing direction is composed of a plurality of blocks each having a predetermined number of sub-pixels as one block.
Arrangement numbers that define the order in which the correction of the K gradation and the correction of the K + 1 gradation are performed in N frames of a period are set from 1 to N, and the arrangement numbers from 1 to N of the arrangement numbers assigned to the sub-pixels of one block are set. 6. The two-screen display device according to claim 5, wherein the number is the same. The sub-pixels of the individual images for the two viewing directions are arranged in a checkered pattern, and the image of the same viewing direction and the pair of red, green, and blue sub-pixels with the same gradation correction are arranged so that one individual image is a V character. 6. The two-screen display device according to claim 5, wherein the other individual image is a Λ character. The sub-pixels of the individual images for the two viewing directions are arranged in a checkered pattern, and the pair of red, green, and blue sub-pixels for the same viewing direction and the same gradation correction are arranged so that the two individual images are in the same direction. The two-screen display device according to claim 5, wherein the two-screen display device is inclined. The sub-pixels of the individual images for the two viewing directions are arranged in a checkered pattern, and the pair of red, green, and blue sub-pixels for the same viewing direction and the same gradation correction are directions in which the two individual images are different from each other. The two-screen display device according to claim 5, wherein the two-screen display device is inclined. The sub-pixels of the individual images for the two viewing directions are arranged in a checkered pattern, and the pair of red, green, and blue sub-pixels for the same viewing direction and the same gradation correction are inclined every other sub-pixel. The two-screen display device according to claim 5, wherein: The sub-pixels of the individual images for the two viewing directions are arranged in a checkered pattern, and the pair of red, green, and blue sub-pixels for the same viewing direction and the same gradation correction are arranged in an odd number of frames and an even number 6. The second frame according to claim 5, wherein the arrangement pattern of the second frame is made different.
Screen display device. The sub-pixels of the individual images for the two viewing directions are arranged in a checkered pattern, and the pair of red, green, and blue sub-pixels for the same viewing direction and the same gradation correction is an odd-numbered or even-numbered frame. The two-screen display device according to claim 5, wherein the other frame is a V character or a Λ character. 6. The two-screen display device according to claim 5, further comprising a selection unit that has a plurality of mixed patterns of the K gradation correction and K + 1 gradation correction areas, and selects the pattern by external input. . The two-screen display device according to claim 1, further comprising a selection unit that includes a plurality of modes having different values of N and selects the mode by external input. In the same gradation, the brightness of the green sub-pixel is higher than that of the red sub-pixel and the blue sub-pixel, and the sub-pixels of the individual images for the two viewing directions are arranged in a checkered pattern, and the image in the same viewing direction The sub-pixel arrangement is characterized in that green sub-pixels are not arranged in the six sub-pixels in the same viewing direction of the upper left, upper right, lower left, lower right, left, and right centering on the green sub-pixel. 5. A two-screen display device according to 5. The sub-pixels of the individual images for the two viewing directions are arranged in a checkered pattern, and three sub-pixels of the same color of K + 1 gradations, where the sub-pixel arrangement in the image of the same viewing direction is performed for one frame K + 1 gradations in N frames. The two-screen display device according to claim 5, wherein the two-dimensional display device is arranged so that it does not move to adjacent pixels continuously by a frame change. One pixel is composed of three sub-pixels of red, green and blue, and gradation display of luminance of the sub-pixel is set, and a two-screen image in which sub-pixels of individual images for two viewing directions are adjacent in the gate line direction A two-screen composition unit for outputting, and a crosstalk correction unit for correcting the gradation of the sub-pixel to be corrected based on the gradation of the adjacent sub-pixel,
The crosstalk correcting unit performs the correction of K (K is an integer) gradation in N (N is a positive integer greater than or equal to 2) N frames (N1 is a positive integer less than N) frame, and the correction of K + 1 gradation is performed. N-
N1 frames are composed of a plurality of blocks in which M1 is one sub-pixel in an image in the same viewing direction, and the order in which the correction of the K gradation and the correction of the K + 1 gradation is performed in N frames of one cycle. The determined array numbers are set from 1 to N so that the numbers from 1 to N of the array numbers assigned to one block of sub-pixels are the same, and the luminance of the green sub-pixel in the same gradation is the red sub-pixel. A two-screen display device having a luminance substantially L times that of a pixel and a blue sub-pixel,
The luminance of the green subpixel is calculated as L times the luminance of the red subpixel and the blue subpixel,
A group in which the number of sub-pixels to be determined and the number of adjacent sub-pixels is a total of M2 is set in one block,
The correction of all the sub-pixels of the one block is performed by correcting the K gradation by N-1 frames, and the K
When the correction of +1 gradation is performed for one frame, the time when the average luminance of one sub-pixel in one group is substantially the same as the average luminance of one sub-pixel in a block for all sub-pixels in one block is N frames. A two-screen display device characterized in that it is an assignment pattern of the array element number to one block at least once. A two-screen image in which one pixel is composed of three sub-pixels of red, green, and blue, the gradation display of the luminance of the sub-pixel is set, and the sub-pixels of individual images for two viewing directions are arranged in a checkered pattern A two-screen composition unit for outputting, and a crosstalk correction unit for correcting the gradation of the sub-pixel to be corrected based on the gradation of the adjacent sub-pixel,
The crosstalk correcting unit performs the correction of K (K is an integer) gradation in N (N is a positive integer greater than or equal to 2) N frames (N1 is a positive integer less than N) frame, and the correction of K + 1 gradation is performed. N-
N1 frames are composed of a plurality of blocks in which M1 is one sub-pixel in an image in the same viewing direction, and the order in which the correction of the K gradation and the correction of the K + 1 gradation is performed in N frames of one cycle. A two-screen display device in which the determined array numbers are set from 1 to N and the numbers from 1 to N of the array numbers assigned to one block of sub-pixels are the same.
The correction of all the sub-pixels of the one block is performed by correcting the K gradation by N-1 frames, and the K
When one frame of correction is performed for +1 gradation, the frame order in which all sub-pixels of one block have the same color sub-pixel of the first adjacent pixel of the determination target sub-pixel as K + 1 gradation, and the determination target The frame order in which the sub-pixel has K + 1 gradation and the frame order in which the sub-pixel of the same color of the second adjacent pixel of the determination target sub-pixel has K + 1 gradation are not sequential.
A two-screen display device, wherein the array number is an allocation pattern to one block.

Images